HONG KONG (REUTERS) - Another top executive is leaving Twitter.

Its China chief Kathy Chen is quitting after just eight months on the job at the microblogging company.

She tweeted: "Now that the Twitter Asia Pacific team is working directly with Chinese advertisers, this is the right time for me to leave the company."

Twitter hired her to lure more Chinese ad clients, but her earlier work with Chinese state-affiliated entities made her the focus of social media criticism.

Twitter has lured top advertisers like smartphone maker Xiaomi, e-commerce giant Alibaba and Air China, making Greater China one of its fastest growing markets in Asia Pacific.

But the social media platform is only available through virtual private networks in China because it has been blocked there since 2009. And China has been calling for greater Internet curbs.

Marbridge Consulting managing director Mark Natkin said: "You are getting more companies who are beginning to question the value of the investments they are making here."

Ms Chen said Twitter is committed to the China market and would keep its Hong Kong office open.